BALOPTICON MODEL C 



'"THE school without a Projection Apparatus is 

 deprived of one of the most useful factors in 

 school work from both an educational as well as 

 social viewpoint. Our Model C is sold at a price 

 which brings it within the reach of every school. 

 (f Send for illustrated circular and pricelist. 



<J Lantern C, complete with Electric Lamp, $50.00 ; 

 with Acetylene Burner, $45.00. 



<| PRISM is a little magazine of lens information. 

 I][ Our name on a Laboratory Apparatus, Photographic Lens, 

 Field Glass, Microscope, Scientific or Engineering Instru- 

 ment is our Guarantee. 



Bausch & Lomb Optical Co. 



Cad Zeiss. Jena 

 Offices 

 New York 

 Boston 



Chicago 



George N. Saegmullet 

 San Francisco 

 Washington 

 London 

 Frankfort 



ROCHESTER. N. Y. 



If you 'want 

 the Best 



CoCOa and 



Chocolate 



in the World 

 insist on getting 



Refracting and Reflecting 



Astronomical Telescopes 



Standard and Portable 



\ 



Visual and Photographic 



OBJECTIVES 



Computed by our associate 



DR. F. R. HOULTON 



{Chicago University) 



OBSERVATORIES 



Specula, Planes, Eyepieces, etc. 



Illustration shows 6 -in. with pneumatic clock. 



Photographs and Circulars on request 

 LOHriANN BROS. 



GREENVILLE, OHIO : : : : U. S. A. 



